TORNADO WARNING issued for parts of central Indiana until 8:15 p.m.

Temperature downturn coming to end the week and the year; Much colder pattern returns soon

RAIN ARRIVING

Our weather takes a turn again late Wednesday.  After sunny skies and a warm up to 48°, clouds have thickened and light rain showers have arrived.  The west to east moving showers will not last long, they are expected to diminish after 12 AM.

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NEW COLD FRONT

A wind shifting cold front (passes through Indianapolis around 1 AM) will sweep the state and deliver colder air for Thursday.  Keeping track of the temperatures, its been a real see-saw.  Starting at 24° Wednesday we warmed to 48° (12 degrees above normal).  We will lower to near freezing by sunrise and hold steady in the upper 30s Thursday afternoon.

Brisk, west-northwest winds will make it feel even colder Thursday.  The wind chill will dip into the teens ate times early Thursday and again Thursday evening.

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SNOW PATROL

We haven't had any measurable snowfall or even a trace in a week in a half, but the combination of colder air, and some sunshine Thursday afternoon could bring to life a few snow showers by evening.  Currently, the timing of a snow shower or two could come closer to the 4 - 5 pm time frame Thursday.  A coating is possible in elect spots especially in eastern and north-central Indiana.

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Snow cover has decreased over the past 10 days.  As of December 28th, 37.5% of the Nation is covered in snow, down from a peak of 54.8% on the 18th.

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NEW YEARS'S WEEKEND

There tug-o-war temperature trend will resume again this weekend with a stalled front wobbling north and south through Sunday evening.  Along the front a few light rain showers are possible starting early afternoon Saturday.  Currently the New year's Eve weather looks damp and cool with temperatures dipping into the upper 30s by midnight.

Light rain showers are expected again Sunday as the front begins a northward migration.  Temperatures Sunday will range from the upper 30s to middle 40s and begin rising late day and into the night.  The warm front will also create some foggy conditions into early Monday morning.

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COLD PLUNGE COMING

The absence of the polar jet stream is ending next week.  Colder air is on the move and we are expecting to cram unseasonable warm and arctic air into the opening days of 2017.  A rise to nearly 60° along with rain is forecast Monday then much colder air will surge into the state starting Tuesday.  Temperatures are expected to fall sharply Tuesday as the jet stream plunges colder air into central Indiana.  Temperatures could stay well below freezing for much of the middle and end of next week.

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U.S. GFS Model upper air forecast next Wednesday. A large dive in the upper air pattern signals much colder air is on the move

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NWS 6-10 day temp probability of colder than normal centered on the week of January 3rd through the 7th